Thermostatic apparatus.



'No. 73,2,6QQ. PATENTED JULY 7, 1903.

' M. s. BELL.

THERMOSTATIG APPARATUS.

APPLICATION FILED AUG. 31, 1901.

E0 MODEL. A 2 SHEETS-GEEK! 1.

min 1,

In 1 lllllllllllll iii No. 732,699. A PATENTBD JULY 7, 1903.

'M SI I V THERMOSTATIG APPARATUS.

APPLICATION FILED AUG. 31, 1901. N0 MODEL 5 BHEETS-SHEET 2.

INVENTUR J M/ V I ATTORNEYS I WITNESSES:

UNITED STATES Patented July 7, 1903.

" PATENT OFFICE.

MAJOR S. BELL, Oi NEW YORK, N. Y.

THERMO STATlC APPARATUS.

SPEGIlEIGATION forming part of Letters Patent No. 732,699, dated July 7,1903. Application filed August 31,1901. Serial No. 73,919. (No model.)

To all whom it may cortcern:

Be it known that I, MAJOR STANLEY BELL, a subject of the King ofGreatBritain and Ireland, residing in the borough of Manhat-' thermostatof any suitable construction that will clearly indicate to the eyewhether the valve or damper admitting the heating fluid is open orclosed. Usually thermostats located in rooms are supplied withthermometers and an arrangement is provided by which a person is enabledto open or close the supply-valve more or less by the action of thethermostat.

'It frequently occurs, however, that the temperature in a room exceedsthe intended temperature, not because the heating fluid controlled bythe thermostat is admitted too freely, but because other temporaryreasons, as an influx of warm air from other rooms, an open fire in theroom, or the like, supply an additional amount of heat independently ofthe radiator fed by the steam or other heating medium. Thus if theoccupant of the room finds too high a temperature and attempts tocorrect it by regulating the thermostat toadmit less heating fluid tothe ra-' diator it may often occur that after the temporary influencesincreasing the heat have ceased to act the radiator will fail to furnishthe required amount of heat. By the use of my invention, as describedhereinafter, it becomes possible and easy to ascertain at any timewhether the excess of temperature is due to the action of the radiatorand has therefore to be corrected by an adjustment of the thermostat oris due to other causes, in which case an adjustment of the thermostat isof course not necessary. I

Reference is to be had to the accompanying drawings, in which.

Figure l is a face view of the thermostat provided with my improvedattachment. Fig. 2 is a similar view thereof with the face-plateremoved, and Fig. 3 is an elevation with parts in section on line 3 3 ofFig. 2.

The instrument shown is a well-known form of thermostat; but I desire itto be understood that my present invention has no reference to thespecific construction of a thermostat proper and any suitable orapproved form may be used. The bar or rod a, which expandsundertheinfluenceof heat and contracts when cooled, controls thecirculation of air which actuates the diaphragm b, which in turncontrols by its action the admission of the heating fluid, this beingeffected through the medium of a spring-pressed lever or yoke c,fulcrumed atd, which in the present case is used to opcrate theindicator; but it will be understood that any other moving part of thethermostat may be used for this purpose. As shown, the moving part-thatis, the yoke c-has a projecting pin 6, which engages the slotted arm ofthe bell-crank lever f, fulcrumed atf' to a bracket f attached to theframe of the in= strument by the screw f and connected at its other endby a link 9 with another bellcrank lever, h, fulcrumed at h upon abracket 77, attached to the frame of the instrument by the screw h Thetwo axes f and h, about which the bell-crank levers f and h swing, arearranged at right angles to each other. The bell-crank lever h carriesthe toothed sector t, engaging a pinion j on an arbor in, carrying apointer l, the arbor It being supported by bearings in the bracket h.This pointer shows through a segmental sight portion m of the backingor support to which the thermometer it is secured. At the loot-v tom ofsaid support is located another pointer or indicator, 0, fulcrumed at 0and adapted to be turned by means of a suitable head 0 this pointerindicating on the graduation or a link connected with said bell-cranklever, another bell-crank lever connected with said link, and having itsaxis disposed transversely of the axis of the first-named bell-cranklever,

a toothed sector carried by the said other bell-crank lever, a pinionengaging said sector, and a pointer or indicator mounted to turn withsaid pinion.

MAJOR S. BELL.

Witnesses:

JOHN LOTKA, EUGENE EBLE.

